Squeeze element



Aug. 22, 1967 S. H. SCHWARTZ 3,336,745

SQUEEZE TDLEMENT Filed July 25, 1966 2 sheets-sneet 1 d@ @fami @a @f7-fw Aug 22, 1967 s. H. SHwA'm-z 3,336,745

SQUEEZE ELEMENT Filed July 25, 1966 2 Sheets-Sheet 2 'F-LE- 5 (p2/oe 4er) United States Patent O 3,336,745 SQUEEZE ELEMENT Samuel H. Schwartz, Deerfield, Ill., assignoi to The Dole Valve Company, Morton, Grove, Ill., a corporation of Illinois .Filed July 2S, 1966, Ser. No. 567,669 10 Claims. (Cl. 60-23) ABSTRACT F THE DISCLOSURE A temperature responsive force transmitting device having a cup member and a guide portion and a resilient boot or diaphragm deployed within a cavity formed interiorly of the cup and guide portions. The cup portion contains a thermally expansible wax or the like and a temperature rise ambient the wax exerts a compressive force on the resilient boot or diaphragm for squeezing a power member or piston outwardly from the boot. An anti-chafe ring is disposed between the uppermost end of the boot and the Iadjacent end wal-l portion of the guide portion of the unit and surrounds the power member piston. The anti-chafe ring has a greater thickness in the vicinity of the power member and has a less thickness at points spaced radially outwardly therefrom and has -angled faces which exert a compressive force about the power member to maintain a continuous seal and to prevent the extrusion of the boot through the opening in the power member guide.

This invention relates to a temperature responsive force transmitting device of the type having a diaphragm. or power member boot which is seated Within a Casin-g and more particularly relates to a novel means for sealing the boot about the power member in the vicinity of the guide opening and for preventing the entry of water or oreignmaterials into the casing through the power member guide and for preventing the resilient boot from abrading or extruding in the vicinity of the guideopening.

Temperature responsive force transmitting devices of the type referred to in this invention generally employ a diaphragm or power member boot which has aperipheral bead compressed between a power member guide portion and, a base cup of the casing. A cavity containing a temperature sensitive expansible material is provided beneath the boot in the base cup and changes in ambient temperature result in an upward pressure on the boot for -actuating a power member within the power member guide.

The power member guide and a neck portion of the resilient boot have cooperable openings formed therein which are suitably aligned for receiving a power member or piston through the guide to be seated internally of the boot. Pressure acting on the lower portion of the boot `within the base cup causes the resilient boot to be compressed for'squeezing the power member from the boot and outwardly of the power member guide. However,

the high pressures created in the base cup of the thermal power unit are transmitted to the neck portion of the boot adjacent the guide opening in the power member guide.

The result is that the resi-lient material for-ming the boot tends to extrude or abrade in the high pressure region immediately adjacent the guide opening of the power member guide. Also, the constant movement of the power piston wears at the edge of the resilient boot adjacent the guide lopening and thereby limits the life of the power unit.

Heretofore a washer type ring, commonly referred to vas an anti-chate ring has been disposed at the end wall vof the boot adjacent the guide opening of the power member, guide to reinforce the edges of the resilient boot which are susceptible to being abraded and extruded 'into the guide opening along with the extension motion of the power member piston.

It has been found, however, that the anti-chate n'ng as heretofore employed in the temperature responsive device has not been entirely satisfactory in that the ring itself is subject to wear due to the repeated movements of the power piston and due to the fact that a ti-ght gripping of the ring about the power member piston has not been possible. It has also been found that the inherent looseness of the anti-chafe ring heretofore employed, allows the entry of water and other foreign substances which may adhere to the power member piston.

Accordingly, it is a principal object of this invention to provide a temperature responsive force transmitting device having a resilient boot tted about a power member and employing a novelmeans for sealing the boot in the vicinity ofthe power member and for preventing the abrading and extrusion of the boot into an associated power member guide bore.

It is another object of this invention to provide a temperature responsive force transmitting device of the squeeze-push element type which provides a novel means for sealing a resilient boot about a power member and for preventing the entry of water and foreign particles into the interior of the power member guide.

It is also an object of this invention t-o provide an antichafe ring for use with a temperature responsive force transmitting device of the squeeze-push element type which has angled action surfaces for developing a compression force component -on the power member for forming a tight seal thereabout and for scraping the power member clean of foreign materials as well as for preventing the abradin'g and extrusion of the resilient boot material into the casing opening through which the power member is guided;

It is also an object of this invention to provide an antichafe ring for a temperature responsive squeeze type power unit wherein the compression of the boot is utilized to develop a radially inwardly directed force on the -anti-chafe ring for tightly sealing the interior of the power unit about the extensible power member.

It is a further object of this invention to provide a temperature responsive fonce transmittingdevice of the squeeze-push element -type whereinthe power member guide has an end wall formed substantially perpendicular to the axis of the power member and wherein the antichafe ring used to clean the power member and to prevent the extrusion and abrading of boot material into the ,power member guide bore has la surface which is mating to the end wall of the power member guide and has an opposite surface which forms an angle with the axis of the power member which angle faces inwardly of the power member guide and which is greater than It is a further object of -this invention to provide a temperature responsivel force transmitting device of the squeeze-push element type having an end wall adjacent the power member guide bore which forms an angle with the axis of the power member which angle faces interiorly of the power member guide and which is less than 90 and wherein an anti-chafe ring has a surface mating with the end wall of the power member guide and has an opposite surface facing interiorly of the power member guide which is substantially perpendicular to the axis of the power member.

It is also an object of this invention to provide a temperature responsive force transmitting device of the resilient diaphragm or boot type structure which has an end wall formed adjacent the powermember guide bore which end wall forms an angle with the power member of less than 90.and which angle faces interiorly of the power member guide and wherein an anti-chate ring has a mating surface disposed anjacent tothe end wall of the power member guide and has an opposing surface which faces interiorly of the power member guide and which forms an angle greater than 90 with the power member which angle also faces interiorly of the power member guide.

These and other objects, featu-res and advantages of the present invention will be understood in greater detail from the following description and the associated drawings wherein reference numerals are utilized in designating a perferred embodiment and wherein:

FIGURE 1 is a sectional view through a temperature responsive force transmitting device according to the present invention showing the assembled orientation of an anti-chafe ring;

FIGURE 2 is an exploded view of the temperature responsive force transmitting device of `FIGURE 1 for more clearly illustrating the inter-relationship of the various components therein;

y FIGURE 3 is a substantially enlarged sectional View o f a portion of a power transmitting device of the type shown in FIGURE 1 employing an anti-chafe ring according to the prior art;

'FIGURE 4 is a sectional view similar to the view of FIGURE 3 showing an anti-chafe ring having the features of this invention;

FIGURE 5 is a sectional view through a temperature responsive transmitting device of the form shown in FIGURES 1 through 4 and illustrating an alternate embodiment of the anti-chafe ringl of this invention; and

FIGURE 6 is a further view similar to the views 3, 4 and 5 and illustrating a fu-rther alternate embodiment of the anti-chafe ring and power transmitting device of this invention.

The temperature responsive force transmitting device of this invention comprises generally a casing assembled in two sections and a resilient power member boot having a peripheral bead sandwiched between those two sections and providing thereby a means for operating a powe-r member. The power member is slidably received within the upper or guide section of the casing and is also received within the upper or guide section of the casing and is also received internally of the resilient boot. A temperature sensitive expansible material, such as expansible wax, is contained within the lower half section of the casing beneath the resilient boot and expansion of the wax exerts a force on the boot for actuating the -power member. Wax of t-he type shown will expand on a temperature rise, however, other elements may be used which would expand on a temperature decline.

The thermal element of this invention is of the squeezepush type. This means that the power member is moved upwardly within its guide due to a compression of -the resilient boot in response to an expansion of the temperatu're sensitive expansible wax contained within the lower half section of the casing. Since the resilient boot is not required to deflect upwardly along with the upward movement of the power member, no deflection space is needed Within the power member guide and the boot structure can be caused to occupy the entire upper portion of the casing. In fact, by causing the boot to fill the entire upper section of the casing, an improved squeezing action is achieved in response to expansion of the temperature sensitive wax.

Referring to the drawings in greater detail, a temperature responsive force transmitting device 10 is shown in FIGURES 1 and 2 as comprising a lower half casing or base cup 11 and an upper half casing or power member guide 12. A power member 13 is disposed within the guide and received internally within a resilient boot 14 which is positionedl wit-hin the casing defined by the cup 11 and the guide 12. The cup 11 is filled with a thermally eXpansible wax 15 and is itself for-med of a thermally conductive material. The wax 15 may take the form of a pellet having a depression 19 which conforms essentially to the outer configuration of the base portion 20 of the resilient boot 14. As is well known in the art, rises in temperature ambient the cup 11 will cause the wax 15 to expand. `Of course, if the wax 15 were an ice element, decreasing temperature would cause the element to expand. This expansion of the wax will be felt through the boot 14 for forcing the power member 13 to move extensibly from the guide 12. Upon cooling in the case of the wax 15, the power member 13 can be returned to a seated position within the boot 14 by a spring means or the like.

As is more clearly shown in FIGURE 2, the base cup 11 has an out-turned annular flange 16 and a vertical annular wall 17 having an inwardly chamfered edge 18. As will be understood the outturned flange 16 and the wall 17 cooperate to form the assembled device of FIG- URE 1.

The flange 16 has a set of V-shaped concentric continuous grooves 21 positioned radially outwardly thereon. A bead 23 of the resilient boot 14 is disposed to overlie the V-shaped concentric grooves 21.

Similar to the construction of the base cup 11, the power member guide 12 has an outturned flange 24 and a rim or annular wall 25. Also, the flange 24 has a series of V-shaped concentric continuous grooves 26 formed radially outwardly thereon. The side wall 27 of the outturned flange 24 is fitted within the annular wall 17 at the inner surface 28. When so seated the V-shaped concentric grooves 26 are radially displaced relative to the grooves 21. This displacement of the V-shaped grooves within the opposing flanges 16 and 24 aids in rigidly positioning the boot 14 within the casing by providing an improved grip -at the bead 23.

The power member guide 12 has a tapered wall section 29 which is received about a conforming tapered wall section 30 of the resilient boot 14. Likewise the guide 12 has a cylindrical wall section 31 which is received about a cooperable cylindrical section 32 of the boot 14. Therefore, the interior of the power member guide 12 is provided to be substantially cooperable with the upper or neck portion 33 of the rubber boot 14 for assuring that the entire volume of the guide cavity will be occupied by the boot.

The power guide 12 has an additional sealing means in the form of additional V-shaped concentric grooves 34 which are formed within the cylindrical section 31. A space 35 is provided above the V-shaped grooves 34 for an anti-chafe ring 36 which is disposed between an end wall 37 ofthe guide 12 and the end wall 38 of the boot 14.

The power member guide 12 has a bore 39 for receiving the cylindrically shaped power member 13 therethrough, and the resilient boot 14 has a well 40 for receiving the lower stem of the power member 13. The power member 13 has a conical end portion 41, and the well 40 of the boot 14 has a spade shaped end section 42. The end configurations 41 and 42 .aid in initiating the squeezing action necessary to actuate the power member 13.

In assembly, the bead 23 of the boot 14 is sandwiched between the outturned flanges 16 and 24 of the base cup 11 and the power member guide 12 for being extruded into the V-shaped grooves 21 and 24 las shown in FIG- URE 1. Also, the diameter of the cylindrical section 32 of the Iboot 14 is substantially larger than the diameter of the cylindrical section 31 of the guide 12, and, therefore, the fitting of the guide 12 about the neck 33 of the boot 14 causes the boot material in the region of the cylindrical section 32 to be extruded into the V-shaped grooves 34. Therefore, an effective seal is provided between 4the flanges 16 and 24 and between the boot 14 and the inner surface of the power member guide 12.

The high pressure which is exerted by the thermal wax 15 as confined within the base cup 11 exerts an upward pressure on the resilient boot 14 and causes the neck portion 33 of that boot to be forced tightly into the cylindrical portion 31 of the power member guide 12. In the absence of the anti-chafe ring 36, for instance, it is clear that the high pressure on the resilient boot at the edge 43, would cause the boot material to ex-trude within the cylindrical lshell region 44 between the piston 13 and the guide lbore 39. This extrusion of the boot material would then cause extensive abrading and wear at the boot and result in an inelfective sealing between the boot material and the power member piston. Accordingly, water and other foreign substances would enter the interior of the boot and disrupt the operation of the temperature responsive force transmitting device.

However, the intention of the anti-chafe ring 36 was to provide a means for preventing the extrusion of the resilient boot material and to prevent the wear at the edge 43 due Ito the extension and retraction motions of the power member 13. However, the extension and retraction of the power member 13 does itself generate wear at the inner surface 45 of the anti-chafe ring 36, and accordingly the anti-chafe ring 45 is less effective for preventing the extrusion of the boot material into the cylindrical region 44 than would otherwise be expected. In substance, the anti-chafe ring as used in the prior art was ineffective for maintaining a tight grip-like seal about the power member piston 13.

FIGURE 3 shows -the prior art anti-chafe ring 46 as disposed within a power member guide 47 which has a guide bore 48 and a power piston 49 operable therein'. The upper portion 50 of a resilient lboot 51 lls a cavity 52 formed at the interior of the power member guide 47 similar to the structure shown in FIGURES 1 and 2.

The arrows in FIGURE 3, however, show that the force which is exerted on the lower surface 52 of the antichafe rin-g 46 due to the compression of the resilient boot 51 isdirected normal to the surface of the anti-chafe ring. This compression force is then resisted by forces genera-ted at the end wall 54 of the power member guide 47. These forces as shown by the arrows are also directed normal to vthe surface of the anti-chafe ring.

Accordingly, in the prior art form as shown in FIG- URE 3, there is no radial lor inward force on the antichafe ring which would tend to compress that ring about the cylindrical surface of the power member 49. The result is that space will be formed such as at 55 between the anti-chafe ring 46 and `the power member 49. This space will allow the extrusion and abrading of the resilient boot 51 in the regions such as at 56 and will accordingly permit the entry of water and foreign substances into the interior of the temperature responsive force transmitting device thereby disrupting the operation of that device. The power transmitting device of FIGURE 4 employing the anti-chafe ring of this invention however, does provide a means for generating a radial force on the power member 49 for preventing the extrusion of boot material between the power member and the Ibore 48.

In particular, the anti-chate ring 57 has a lower surface 58 which is facing interiorly of the power member guide 47 and which is formed substantially perpendicular to the axis of the power member 49. The end wall '59 of the power member guide 47, however, is not formed perpendicular to the axis -of the power member 49, but rather, is formed at an angle to that axis such that a radial force may be generated inwardly on the anti-chafe ring 57. It will be noted that the angle cp which is formed between the end wall 59 and the axis of the power mem- `ber 49 and which faces interiorly of the power member guide 47 is less than 90.

In the anti-chafe ring 57 in addition to having the surface 58 has a surface 60 which is also angled and which is complementary to the end wall 59 of the power member guide 47. This relationship between the surface 60 and the end wall 58 may be said to be mating, and the result is shown generally by the arrows in FIGURE 4.

In particular, the forces F1 which are generated due to the compression of the resilient boot 51 are directed normal to the surface 58 of the anti-chafe ring 57. The forces F1 are then balanced by forces F2 which have -force components F3 which are directed radially inwardly toward the power member 49. This inward radial component exerts a force on the power member 49 which effectively seals the space between the power member and the anti-chate ring `and which causes the anti-chafe ring to scrape the power member 49 for maintaining the surface thereof free of excess foreign materials. This action prevents the abrading and extrusion of the resilient boot 51 which occurs in the prior art structure of FIGURE 3.

FIGURE 5 shows a further embodiment of the antichafe ring of this invention. In particular, the anti-chafe ring 57 has a surface 61 which is facing outwardly of the interior of the power member guide 47 and which is formed substantially perpendicular to the axis of the power member 49. Similarly, the end wall 62 of the power member guide 47 is formed mating tothe surface 61 of the anti-chafe ring 57 and is therefore perpendicular to the axis of the power member 49.

However, the opposite face 63 of the anti-chafe ring 57 is angled relative to the axis of the power member 49 and forms an angle 0 which is greater than 90 and which is directed inwardly of the power member guide 47. Forces which are generated by the resilient boot 51 are directed normal to the surface 63 of the anti-chafe ring 57, and these forces F4 have a component F5 which is directed radially inwardly toward the power member 49 and which therefore performs the function described in connection with FIGURE 4, namely the function of tightly sealing the anti-chafe ring 57 about the outer surface of the power member 49.

Another embodiment of the anti-chafe ring 57 and the power member guide 47 is shown in FIGURE 6. In that ligure, the anti-chate ring 57 has an angled surface 64 which is formed to be mating with an angled end wall 65 of the power member guide 47. This surface forms an angle with the axis of the power member 49 which is less than and which is facing inwardly of the interior of the power member guide 47. The opposing surface 66 of the anti-chate ring 57 is directly interiorly of the power member guide and forms an angle 'y with the power member guide which is greater than 90.

The effect of the shaping of the anti-chate ring 57 of FIGURE 6, is that the forces F6 directed normal to the surface 66 of the anti-chate ring 57 due to the com-pression of the resilient boot 51 have radial force components F7 which are directed properly for generating the squeez ing action of the anti-chate ring as described in conjunction with FIGURES 4 and S. Also, the forces F8 which are opposing to the forces F6 and which are generated by the angled end wall 65 of the power member guide 66 also have a radial component F9 which is directed inwardly toward the power member 49 for further assuring that a tight seal will be effected about the power member and for scraping the power member clean upon the extension and retraction thereof and for preventing the abrading and extrusion of the resilient material comprising the boot 51 at the critical region in the vicinity of the power member.

It will be understood that these embodiments of the present invention have been used for illustrative purposes only and that various modifications and combinations of the features of this invention may be eifectediwithout departing from the spirit and scope of the novel-concepts set forth herein.

I claim as my invention:

1. A temperature responsive force transmitting device comprising:

a housing having a base cup portion and a power member guide, said base cup portion ``containingy a temperature sensitive expansible material land said power member guide having a guide opening formed therein;

a resilient boot deployed within said housing and forming a common sealing wall between said base cup and said power member guide;

said boot having Ia neck portion extending within said power member guide;

a power member slidably received within said guide opening and disposed within said neck portion of said boot for being actuated by the expansion of said temperature sensitive expansible material;

a substantially non-resilient anti-chafe ring disposed within said housing about said power member and between said neck portion of said boot and the inwardly facing end wall of said power member guide forming said guide opening, and

said anti-chafe ring having a greater thickness in the vicinity of the power member and having less thickness at points spaced radially outwardly therefrom,

whereby pressure of said boot on said anti-chafe ring urges said ring toward said power piston.

2. A temperature responsive device in accordance with claim 1 wherein the neck portion of the boot has an end Iwall disposed adjacent to the end wall of the power member guide and wherein said anti-chafe ring is disposed between the end wall of the boot and the end wall of the guide for tightly engaging the power member in response to pressurized movement of the boot toward the end wall of the guide.

3. A temperature responsive device in accordance with claim 1 wherein said anti-chafe ring comprises a wafer shaped seal ring having a bore formed centrally thereof and having a cross section which tapers from a greater thickness at the bore to a lesser thickness `at the outer periphery thereof.

4. A temperature responsive device in accordance with claim 2 wherein said end wall of the power member guide and said end wall of the boot having relatively angled surfaces which cooperate with mating surfaces of the antichafe ring for transferring forces created by the boot normal to the anti-chafe ring into forces exerted on the anti-chafe ring having force components perpendicular to the axis of the power member.

5.. A temperature responsive device in accordance with claim 3 wherein the end wall of the power member guide is formed substantially perpendicular to the axis of the power member .and wherein the 'anti-chafe ring has a first action surface mated with the end wall of the power member guide and a second action surface facing inwardly of the guide and mated with the end wall -of the boot wherein said second action surface tapers from a thick portion at the bore to a thin portion at the outer periphery of the ring.

6. A temperature responsive device in accordance with claim 3 wherein the end wall of the power member guide forms an inwardly facing angle with the axis of the power member which is less than' 90, and wherein the antichafe ring has a first -action surface mated with the end wall of the power member guide and a second action surface facing inwardly of the guide and mated with the end wall of the boot wherein said second action surface is formed substantially perpendicular to the axis of the power member.

7. A temperature responsive device in accordance with claim 3 wherein the end wall of the power member guide forms an inwardly facing angle with the axis of the power member which is less than 90, and wherein the antichafe ring has a first action surface mated with the end wall of the power member guide and a second action surface facing inwardly of the guide and mated with the end w-all of the boot wherein said second action surface tapers from a thick portion at the bore to a thin portion at the outer periphery of the ring and forming an inwardly facing angle with the axis of the power member which is greater than `8. A temperature responsive force transmitting device comprising:

a base cup containing a temperature sensitive expansible material and having an outturned ange;

a resilient boot having an integral annular bead formed therearound and overlying said ange;

a power member guide having an outturned flange mounted at said outturned ange of said base cup;

said bead secured between said anges;

a guide opening formed within said power member guide;

a power member mounted for rectilinear movement Within said guide opening and disposed within said boot for being actuated by said temperature sensitive expansible material;

a substantially non-resilient anti-chafe ring mounted about said power member and sandwiched between said boot and said power member guide;

said anti-chafe ring having a greater wall thickness immediately adjacent thev power member -and being tapered to a lesser wall thickness at the outer periphery thereof.

9. A temperature responsive force transmitting device in accordance with claim 8 wherein said anti-chafe ring has a surface abutting the boot and facing generally inwardly of the power member guide and wherein said surface forms an angle greater than 90 with the axis of the power member.

10. A temperature responsive force transmitting device comprising:

a base cup formed of a heat exchange material and containing a temperature sensitive expansible material and having an outturned fiange;

a resilient boot having an integral annular bead formed therearound and overlying said iiange;

said resilient boot having a base portion depending into said base cup and a neck portion extending upwardly therefrom;

a power member guide fitted tightly about said neck portion of said boot and having an outturned ange connected to said vflange of said base cup for compressing said annular bead of said boot between said flanges;

said neck portion of said boot filling the available inner volume of said power member guide;

a power member guided for rectilinear movement within said guide and received within said boot;

a substantially non-resilient anti-chafe ring fitted about the power member and sandwiched between the neck portion of the boot and a wall of the power member guide; and

said anti-chate ring having a surface abutting the boot which is angled relative to an opposite surface abutting the power member guide for transposing forces created by the boot normal to the anti-chate ring into forces exerted on the anti-chafe ring which forces have components perpendicular to the Iaxis of the power member.

References Cited UNITED STATES PATENTS 7/1940 Vernet 60-23 X 1/1962 Vernet 60-23 X 

1. A TEMPERATURE RESPONSIVE FORCE TRANSMITTING DEVICE COMPRISING: A HOUSING HAVING A BASE CUP PORTION AND A POWER MEMBER GUIDE, SAID BASE CUP PORTION CONTAINING A TEMPERATURE SENSITIVE EXPANSIBLE MATERIAL AND SAID POWER MEMBER GUIDE HAVING A GUIDE OPENING FORMED THEREIN; A RESILIENT BOOT DEPLOYED WITHIN SAID HOUSING AND FORMING A COMMON SEALING WALL BETWEEN SAID BASE CUP AND SAID POWER MEMBER GUIDE; SAID BOOT HAVING A NECK PORTION EXTENDING WITHIN SAID POWER MEMBER GUIDE; A POWER MEMBER SLIDABLY RECEIVED WITHIN SAID GUIDE OPENING AND DISPOSED WITHIN SAID NECK PORTION OF SAID BOOT FOR BEING ACTUATED BY THE EXPANSION OF SAID TEMPERATURE SENSITIVE EXPANSIBLE MATERIAL; A SUBSTANTIALLY NON-RESILIENT ANTI-CHAFE RING DISPOSED WITHIN SAID HOUSING ABOUT SAID POWER MEMBER AND BETWEEN SAID NECK PORTION OF SAID BOOT AND THE INWARDLY FACING END WALL OF SAID POWER MEMBER GUIDE FORMING SAID GUIDE OPENING, AND SAID ANTI-CHAFE RING HAVING A GREATER THICKNESS IN THE VICINITY OF THE POWER MEMBER AND HAVING LESS THICKNESS AT POINTS SPACED RADIALLY OUTWARDLY THEREFROM, WHEREBY PRESSURE OF SAID BOOT ON SAID ANTI-CHAFE RING URGES SAID RING TOWARD SAID POWER PISTON. 